The 25-year-old singer took to the stage towards the end of The Special’s set – the ska band that Amy grew up idolising – and belted out a rendition of the group’s hit You’re Wondering Now before providing the backing vocals to another track, Ghost Town.

With a healthy glow in her cheeks and no longer looking like the frail star of previous months, Amy delighted fans with her incredible voice and seemed to be on top form following her prolonged break away from the limelight.

The beehived diva’s appearance wasn’t the only highlight of the popular festival.

US country-pop singer Taylor Swift rocked it out wearing a black tasselled dress while Katy Perry wowed with an energetic set featuring all her hits.

The Hot and Cold hitmaker donned yet another incredible outfit for the occasion – this time, a strawberry-inspired two piece that showed off her enviable figure.